Answer:
a line of symmetry is a line divide an object in to two equal parts. answer is A
Looks good to me.
Step-by-step explanation:
KE = ½mv²
KE₁₀ = ½(1100)10² = 55000 = 55 kJ
KE₃₀ = ½(1100)30² = 495000 = 495 kJ
9 times greater